Adhesive hydrogels and uses thereof

Abstract

Adhesive hydrogels comprising a (co)polymer matrix, wherein the adhesive hydrogel comprises at least one rough surface as well as processes for preparing such hydrogels are disclosed.

The invention claimed is: 
     
       1. An adhesive hydrogel comprising a (co) polymer matrix, wherein the adhesive hydrogel comprises at least one rough surface that includes at least one feature having a height of from about 50 micrometers to about 200 micrometers measured perpendicular to a plane in which the adhesive hydrogel lies,
 the rough surface having a topography characterized as being a peak-valley topography, 
 the (co) polymer matrix comprising any one or more of (i) a homopolymer or a copolymer of 2-hydroxyethyl methacrylate, (ii) a homopolymer of poly(ethylene glycol) diacrylate or of poly(ethylene oxide), (iii) a copolymer of poly(ethylene glycol) diacrylate or of poly(ethylene oxide), (iv) a homopolymer or a copolymer of poly(propylene oxide), (v) a homopolymer of a copolymer of poly(acrylic acid), (vi) a homopolymer or a copolymer of poly(vinyl alcohol), or (vii) a polysaccharide-based (co) polymer, 
 wherein the topography of the rough surface is randomly arranged, and 
 wherein valleys of the peak/valley topography form a randomly-arranged network of microchannels that allow fluids to drain from contact points between a substrate when contacted to the adhesive hydrogel. 
 
     
     
       2. The adhesive hydrogel of  claim 1 , wherein the adhesive hydrogel further comprises at least one smooth surface. 
     
     
       3. The adhesive hydrogel of  claim 1 , wherein the adhesive hydrogel comprises two rough surfaces. 
     
     
       4. The adhesive hydrogel of  claim 3 , wherein each of the two rough surfaces are situated on opposites sides of the adhesive hydrogel to each other. 
     
     
       5. The adhesive hydrogel of  claim 1 , wherein the (co) polymer matrix comprises a homopolymer or copolymer of 2-hydroxyethyl methacrylate. 
     
     
       6. The adhesive hydrogel of  claim 5 , wherein the (co) polymer matrix comprises a copolymer of 2-hydroxyethyl methacrylate and poly(ethylene glycol) diacrylate. 
     
     
       7. The adhesive hydrogel of  claim 2 , wherein the root mean square roughness of the at least one rough surface is at least one order of magnitude higher than the root mean square roughness of the at least one smooth surface. 
     
     
       8. The adhesive hydrogel of  claim 1 , wherein the (co) polymer concentration is less than 32 weight %, based on the total weight of the adhesive hydrogel. 
     
     
       9. The adhesive hydrogel of  claim 1 , wherein the (co) polymer concentration is from 28 to 32 weight %, based on the total weight of the adhesive hydrogel. 
     
     
       10. The adhesive hydrogel of  claim 1 , wherein the (co) polymer matrix comprises N-isopropyacrylamide 2-(dimethylamino)ethyl methacrylate. 
     
     
       11. A process for preparing the adhesive hydrogel of  claim 2 , comprising the steps of:
 (1) providing a reaction mixture comprising at least one monomer and water; 
 (2) charging a container comprising a smooth interior surface with a volume of the reaction mixture, such that the volume of the reaction mixture is less than the volume of the container; and 
 (3) covering the charged container with a lid and polymerizing the at least one monomer in the presence of the water to obtain the adhesive hydrogel comprising at least one rough surface and at least one smooth surface. 
 
     
     
       12. A process for preparing the adhesive hydrogel of  claim 3 , comprising the steps of:
 (1) providing a reaction mixture comprising at least one monomer and water; 
 (2) charging a container comprising a rough interior surface with a volume of the reaction mixture, such that the volume of the reaction mixture is less than the volume of the container; and 
 (3) covering the charged container with a lid and polymerizing the at least one monomer in the presence of the water to obtain the adhesive hydrogel comprising two rough surfaces.